Dr Horrible 2!

Slightly late on this one, but only just found it:

Doctor Horrible Sequel, Soundtrack Planned by Michael Hinman
(from SyFy Portal)

The soundtrack's already been released, but it's good to hear there'll be a sequel as the first three episodes of Dr Horrible's Sing-Along Blog were fantastic.

I can't wait for the DVD either:

"the writing crew already is preparing for a DVD release, which will be far more than simply 45 minutes of Whedon musical talents. "You probably heard about Commentary: The Musical," Jed Whedon said. "If you haven't, there is going to be commentary that we're writing songs for." There also will be a chance for fans to be involved. The crew is preparing to accept video from fans featuring their character they would like to be accepted into the Evil League of Evil. The 10 best videos will be picked and included in the DVD release."

Also, in a more random incident, Dr Horrible's van remote can be found online here. You'll need an iPhone to appreciate that at it's best though.